Development and production of modern large caliber cannon require tests reliably simulating firing conditions of intended use. Thus, present general practice involves loading a cannon with solid propellant and igniting it to Produce high pressure gas consisting largely of carbon monoxide and carbon dioxide at temperatures between 3400.degree. F. and 4050.degree. F., and repeating the operation a predetermined number of times or until the cannon bore exhibits significant metal transformation. This is an expensive and time consuming procedure, typically involving at least a year or two and cost in millions of dollars for each complete test run of a cannon test specimen.